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XP256; pvtimeouts and queue depth

XP256; pvtimeouts and queue depth

I'm hoping to get some honest feed back here, from customers using the XP256, preferably connected in a SAN environment, with switches.
We've got the XP, with just an R1 cabinet, almost full, all 47 gig disks, configured as Open-9s. We're FC attached from the A, E, and J ports to a pair of brocade switches. Off the switches we've got fc attached a K460, K570, and 3 N4000 servers. The two K's are running flat file JFS file systems, while the N's are our SAP environment. On only the K460 we're fighting regular LVM PowerFail events, 99% of the time it's 2 ldevs involved, and they always report back in within the same second of the PF events. We've attempted to replicate the problem on the K570, no such luck, it behaves exactly as we expect it to-great!
All pvtimeouts are set to the default, as is the queue depth. We've found that extending the pvtimeout only serves to quiet the PowerFail messages, the affected process runs 5-10 times as long as it does with the powerfails.
Is anyone else seeing oddities similar to this, and if so, what are your pvtimeouts set to, and queue depth?
Many thanks to all who respond!
1 REPLY
Philippe GAUQUELIN
Occasional Visitor

Re: XP256; pvtimeouts and queue depth

We had also this problem with similar config (hub and not switch for SAN). I modify pvtimeout to 60 and qdepth to 2. Since that we have no more message. This value MUST be reset at each boot. So we add and /sbin/init.d/initdsk with /etc/rc.config.3/Sxxxinitdsk link.
Thind these script as attachment . Qdepth is configurable so that total qdepth is less than 256 on one FC link.
Here is the config file of attached script:
# config init de physical volumes pour XP256
# racine de l'adresse des disques
export ADDISK=c6t
# time out PV
export PVTO=60
# Q DEPTH "normale"
export QDEPTH=2
# Q DEPTH "speciale"
export SQDEPTH=2
# liste des device avec une QDEPTH speciale
# attention le nb total de qdepth doit etre < 256 par device
# pour temp tape4 tape2
#export LDEV="c13t3d3 c13t0d2"
export LDEV=""